How Do You Use Texture Masks?

I am 100% new to UE4 . So, to sum it up, I’m trying to create a brick. Yes, just one single clay brick. I’ve got the mesh object and I’ve got some brick textures I like and I know how make a material with one and slap it onto my brick.

The issue is, my brick needs different textures on each side rather than 1 texture all over. I’ve read the documentation on Texture Masking about 12 times now and it’s just all black magic to me. Can someone try to make it clearer?

I managed to create a simple mask and was able to apply two different textures on specific parts of the object, but this effect was created on every side. Do I simply need to create my brick in Maya or something that’s made for these things?